furnace dying?

I have a Bryant furnace in my home (it has plus 90 sticker on it). Not sure how big. House is 3500 sq ft and 17 yrs old. Furnace makes occasional squeaking noise and is getting a little worse (doesn't make noise all the time when it kicks on). Also seems to go on a little more than normal, but shuts off rather quickly at times as well. It's my first winter in this house. Just looking for guidance on what to look for if my furnace is dying. Is this something that can be fixed with a tune up possibly?